Stethoscope.



G. J. FILLING.

APILIOATZGI PILED 001'. 18. 1006.

Patented Jan. 26, 1909.

INVEN TOR i r} l.

Y E N R O T T A WITNESSES UNITED sTAtr s PATENT OFFICE.

No. e1e,sa4.

sise'emeaaaa a: Letters intent. Application nan Gotcha-1S, moo. Bel-la! m. seam.

releases-ares. as, 1961:.

Th all whom it may comm.-

Be it known that I, CHARLES J. PILL'ING a citizen of the United States, residing in t e city of Philadelphia, State of Pennsylvania, have invented certain new and useful Imrovements in Stethoscopes of which the ollowing is a full, clear, and exact description, reference being bad to the accompanying drawings, forming a part of this specification.

M invention relates to stethoscopes and has or its object the better and more complete reception and transmission of soundwaves created by its diaphragm when set in vibration.

To this end my improved instrument comrises a suitable supporting means for a viratable diaphragm, and forming part of a casin of a character to sup ly a shallow soun chamber, of a back or base plate the inner face of which has a central c rcular concavity with a spiral concavity surrounding and communicating with the sanie, an a erture in said central concavity, exten ing through the base late, and a sound-conveying tube mounted in said aperture. In its best form I prefer to make such sound-conveying tube as a forked tube, of metal and hence rigid, with its inlet end curved so as to cause it to lie in a lane substantially arallel with the back 0 the baseplate an with its end screw-threaded to fit a screw-thread on the aperture of the base plate; but these special features are not claimed herein.

In the drawings illustrating my improved device Figurel 1s a plan view of the device with the rubber ends, detached, of the usual binaural flexible tubes connected thereon. Fig. 2 is a side elevation thereof. Fig. 3 is a plan view of the underface of the base plate of the instrument; Fig. 4 is a vertical sectional view of the instrument sho 0 also in elevation one form of and method of connecting the rigid sound-conveying tube. 5 is a plan view and Fig. 6 a sectional view, partly in elevation, of another form of the ass-plate and of the mounting thereon of theri id sound-conveyin tube.

Re erring now to said drawin 2 indicates the back or exterior of the see plate, and mounted thereon through an aperture 7 in the re 'on of a central concavity 8 therein is the i at end 3 of a rigid metallic soundconve tube 4 ha integral forked bran es 4, 4, to the ends 0 which may be removably attached the flexible tubes 5, 5, of a Imam term at binaural device 6. The inlet end of the tube 4 is referably curved downwardly, as shown in 'gs. 2, and 6, in order to bring the tube into substantial arallelism with the back of the base-plate, he forked discharge ends extending beyond the annular rim thereof; though, as shown in Figs. 2 and 4, the single tube 4 may be substituted, mounted in an inclined position relatively to the base-plate, entering an aperture 7 on and towards the side of the central concavity 8 thereof 5 but the forked form of rigid soundconveying tube before described, is preferable, and in such case its inlet end 3 is screwthreaded at 7 (Fig. 6), the aperture 7 in the base-plate is threaded to correspond, and a flange plate 6 mounted on the end 3 be and the screw threads in order to seat on the aseplate, as shown in Figs. 5 and 6, and in that case the aperture 7 is centralin the concavity 8 as shown in Figs. 1, 2, 6 and 7.

The stethoscope body consists of a back or base plate 2 constructed as illustrated in the several figures in which the inner face thereof is rovided with means to accumulate and de ect the sound waves produced in the sound chamber of the instrument by the vibration of its diaphragm; these means consisting of a spiral groove on said inner face of the base plate, formin ribs 9 and consequently a series of sha low chambers 9, between them, resultin from the spiral groove in the face of the p ate; the spiral ove proceeding from the outer circular e ge of the plate towards the center and terminating in a central circular concavity 8, forming a. secondary sound chamber from which the sound waves are discharged throu h an aperture 7 therein, and which may e central thereof, as in Figs. 1 and 2, or at the side thereof as in Fig. 4, depending on which of the two described forms of rigid sound conveying tube is employed. Peripherally mounted on this base-plate 2, such as by coacting screw threads, is a ring 10 hav' an inwardly projecting flange 11 adapts to support the usual vibratable diaphr m 12 by compressing its extreme annu ar e go or run between such flange and the annular edge or rim of the base plate 2, the ring 10 being of such width that when the parts are assembled there will be a shallow space, forming the usual sound chamber space between the diaphra and the inner face of the base plate in a dition to the s iral concavity and central concavity, in t e latter.

Having thus described my invention I claim as new and desire to secure by Letters Patent A stethoscope provided with a diaphragm,

5 an annular ring sup ortin the same, and a base plate the inner ace 0 which is rovided with a central circular concavity wit a spiral concavity surrounding and communicating with the same, said elements forming in com-- 10 bination a sound-chamber. with a sound-core tube mounted an aperture in said b se p ate and commumcating with the central concavity therein.

In testimony whereof, I have hereunto aflixed my signature this 29th day of Sep- 15 tember A. D. 1906.

CHARLES J. PILLING.

Witnesses:

Cass. W. MILLER, A. M. BmnLn. 

